ExPBKDF2

Rust NIf for Password-Based Key Derivation Function v2 (PBKDF2). It uses the pbkdf2 rust library.

Installation

The package can be installed by adding ex_pbkdf2 to your list of dependencies in mix.exs:

def deps do
  [
    {:ex_pbkdf2, "~> 0.3"}
  ]
end

The minimum supported rust version is 1.51

Usage

EXPBKDF2 provides three functions:

• generate_salt/1 - generates salt that can be used in pbkdf2/2
• pbkdf2/2 - hashes the provided password
• verify/3 - verifies the hash

generate_salt/1

generate_salt/1 accepts one parameter - format_flag. if it's true, the salt is encoded into b64 format, otherwise, a raw binary is returned.

ExPBKDF2.generate_salt(true)
\\ "SqeHk0Kbypmuj0lPVQsIpA"

ExPBKDF2.generate_salt()
\\ <<86, 203, 205, 255, 49, 164, 123, 49, 106, 130, 250, 222, 107, 90, 58, 9>>

pbkdf2/2

pbkdf2 accepts two parameters - password and optional parameters map. The optional parameters include:

• :salt - if it's not set, it will be generated
• :alg - the hashing algorithm to be used. it can be "sha512" or "sha256". Default value is "sha512"
• :iterations - the number of iterations. The default value is 4096
• :length - the length of the result. The default value is 64
• :format - boolean flag. if it's true, the result will be returned in b64 format, otherwise, it will be returned as raw binary. The default value is false.

opts = %{salt: "salt", alg: "sha256", iterations: 4096, length: 32, format: true}
ExPBKDF2.pbkdf2("password", opts)
\\ "xeR41ZKIyEGqUw22hFxMjZYok6ABzk4RpJY4c6qYE0o"

verify/3

verify/3 accepts three parameters:

• hash - hash generated with pbkdf2
• password - used password
• optional parameters map - it's almost the same as options for pbkdf2, the only exception is format flag is not needed.

opts = %{salt: "salt", alg: "sha256", iterations: 4096, length: 32}
hash = Base.decode64!("xeR41ZKIyEGqUw22hFxMjZYok6ABzk4RpJY4c6qYE0o", padding: false)
password = "password"

ExPBKDF2.verify(hash, password, opts)
\\ true

Benchmarks

This NIF is 5 times faster than pbkdf2_elixir - 4.48 ms vs 22.89.ms. It also performs better in terms of used memory. Benchmarks can be found in the benchmarks directory

Contributing

1. Fork it!
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request

Author

Ayrat Badykov (@ayrat555)